by Playfuls Staff |
28th December 2006
Laptops are known to be extremely sensitive to energy consumption, so the race for finding an (almost) inexhaustible source of energy has always been a main preoccupation for laptop producers. Samsung seems to have taken the lead in this domain.[more]
According to Akihabaranews, Samsung is already offering a high density storage system based on fuel cell technology. A fuel cell is an electrochemical energy conversion device. It produces electricity from external supplies of fuel (on the anode side) and oxidant (on the cathode side). These react in the presence of an electrolyte. Generally, the reactants flow in and reaction products flow out while the electrolyte remains in the cell. Fuel cells can operate virtually continuously as long as the necessary flows are maintained.
Fuel cells differ from batteries in that they consume reactants, which must be replenished, while batteries store electrical energy chemically in a closed system. Additionally, while the electrodes within a battery react and change as a battery is charged or discharged, a fuel cell's electrodes are catalytic and relatively stable.
Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include air, chlorine and chlorine dioxide.
In the archetypal example of a hydrogen/oxygen proton exchange membrane fuel cell (PEMFC), a proton-conducting polymer membrane, (the electrolyte), separates the anode and cathode sides.
On the anode side, hydrogen diffuses to the anode catalyst where it dissociates into protons and electrons. The protons are conducted through the membrane to the cathode, but the electrons are forced to travel in an external circuit (supplying power) because the membrane is electrically insulating. On the cathode catalyst, oxygen molecules react with the electrons (which have traveled through the external circuit) and protons to form water. In this example, the only waste product is water vapor and/or liquid water.
In addition to pure hydrogen, there are hydrocarbon fuels for fuel cells, including diesel, methanol (direct-methanol fuel cells) and chemical hydrides. The waste products with these types of fuel are carbon dioxide and water.
The materials used in fuel cells differ by type. The electrode/bipolar plates are usually made of metal, nickel or carbon nanotubes, and are coated with a catalyst (like platinum, nano iron powders or palladium) for higher efficiency. Carbon paper separates them from the electrolyte. The electrolyte could be ceramic or a membrane.
A typical fuel cell produces about 0.86 volts. To create enough voltage, the cells are layered and combined in series and parallel circuits to form a fuel cell stack. The number of cells used is usually greater than 45 but varies with design. (http://en.wikipedia.org/wiki/Fuel_cell)
Samsung claims that the fuel cell offers an energy density of 650Wh/L, which is about four times as much as competing offerings. The total energy storage is an impressive 12,000Wh which, depending on the laptop's power settings and usage could theoretically power the laptop continuously for a whole month without the need for recharging.
The South Korean electronics giant made the demonstration on its Sense Q35 laptop. Assuming a laptop usually runs for eight hours a day five days a week, the fuel cell can operate it for a month.
The fuel cell system is also said to be very quiet, the level of noise emitted being close to an actual laptop. Although fuel cell batteries have been demonstrated before, the mass production was hindered by the noise and the dimensions and weight of such devices, which would cancel the notion of “portability” for laptops. Samsung is also prepping a mini version of the fuel cell which uses around a coffee cup's worth of fuel, but can still power a laptop for over 15 hours.
Samsung plans to mass-produce the new energy system sometimes at the end of 2007, when all the safety standards are ready.
